The disclosure relates to a power split gearbox, in particular for a motor vehicle, having a mechanical power branch and a hydrostatic power branch which, arranged in parallel to one another, are in contact with a common drive shaft, the hydrostatic power branch comprising a hydraulic motor which is coupled to a hydraulic pump and being connected to the drive shaft via a gearwheel stage, it being possible for the branched power from the mechanical and hydrostatic power branch to be routed together into a gear drive which is arranged on the end side and is connected subsequently by an output shaft, the mechanical power branch comprising two epicyclic gear mechanisms with sun gears, planetary gears and internal gears, the sun gear of the first epicyclic gear mechanism being positioned directly on the drive shaft, whereas the sun gear of the second epicyclic gear mechanism is in contact with the gear drive via a sun gear shaft, and the planetary gears of both epicyclic gear mechanisms being arranged coaxially and being mounted on a common planetary carrier shaft, the planetary carrier shaft on the side of the first epicyclic gear mechanism being mounted via a planet spider in the internal gear of the first epicyclic gear mechanism, and a clutch being arranged on the side of the second epicyclic gear mechanism.
A power split gearbox of this type is known from DE 10 2008 021 010 B4. In addition to a first epicyclic gear mechanism, said power split gearbox has a second epicyclic gear mechanism, the planetary gears of which can be connected via a clutch to the sun gear shaft of the second epicyclic gear mechanism.